When I was a kid, I used to listen to my grandfather's AM tube radio.
It was a breadbox sized Philco, I believe vintage 1940s. It had
excellent reception and excellent sound due to a big old 6x9 inch
speaker on the bottom. I would like to get me a am tube radio. I see
lots on ebay in various conditions, many pretty cheap. But I know
nothing about them, what is good and what is not. Where can I learn
more?